DEVELOPMENT OF OXIDATION CATALYSTS UTILIZING CHARACTERISTICS OF HETEROPOLY COMPOUNDS

1.合成并表征了单、双、三种铁取代聚氧乙烯酸盐。过氧化氢的利用效率和活性很大程度上取决于铁中心，并且基于所使用的底物，二铁取代的聚氧乙烯酸盐γ-SiW_<10>{Fe（0H_2）}_20_<38>^<6->显示出最高的过氧化氢利用效率和转化率。值得注意的是，过氧化氢对含氧产物的利用率高达约10%。dr-铁取代的多金属氧酸盐催化环己烷氧化的反应效率为100%。如此高的效率从未被报道过。在γ-SiW_ {Fe（OH_2）}_2O_（2-x）催化氧化环己烷、正己烷、正戊烷和金刚烷的反应中，H_2O_2的利用率都很高，甲烷氧化为甲醇<10><38>的反应也很成功<6->。研究还表明，二铁取代聚氧乙烯酸盐在所用条件下和过氧化氢存在下是稳定的.已发现Keggin型杂多酸盐催化异丁烷与分子氧的选择性氧化。Cs和V的优选含量分别为2.5和1，并且Ni的添加提高了催化剂对异丁烷氧化的活性。Ni的优选含量为0.08。结果表明，异丁烷氧化是一个表面型反应，催化剂的活性受催化剂表面氧化能力的控制。Cs2.5Ni0.08H1.34PVMo11O4O对丙烷的氧化也有催化作用。

1. Mono-, di-, and tri-iron-substituted polyoxometalates were synthesized andcharacterized. The efficiency and activity for the utilization of hydrogen peroxide greatly depended on the iron centers and the di-iron-substituted polyoxometalate, gamma-SiW_<10>{Fe(0H_2)}_20_<38>^<6->, showed the highest efficiency of hydrogen peroxide utilization and conversion based on substrates used. It is remarkable that the efficiency of hydrogen peroxide utilization to oxygenated products reached up to ca. 100% for the oxygenation of cyclohexane catalyzed by dr-iron-substituted polyoxometalate. Such a high efficiency has never been reported. Not only cyclohexane but also n-hexane, n-pentane, and adamantane were catalytically oxygenated with high efficiency of hydrogen peroxide utilization.Methane was also oxygenated to methanol by using gamma-SiW_<10>{Fe(OH_2)}_2O_<38>^<6->. It was also suggested that di-iron-substituted polyoxometalate was stable under the conditions used and in the presence of hydrogen peroxide.2. Keggin-type heteropolymolybdates have been found to catalyze the selective oxidation of isobutane with molecular oxygen. The preferable contents of Cs and V are 2.5 and 1, respectively, and the addition of Ni enhanced the catalytic activity for the oxidation of isobutane. The preferred content of Ni was 0.08. It was shown that isobutane oxidation is a surface-type reaction and the catalytic activity is controlled by the oxidizing ability of the catalyst surface. Cs2.5Ni0.08H1.34PVMo11O4O also catalyzed the oxidation of propane.